The present invention relates generally to a barrier for absorbing the energy of impact of a moving object and, more particularly, to an impact energy absorbing barrier for decelerating and redirecting a moving object, such as a vehicle, upon impact with the barrier.
Almost all automobile racetracks have a perimeter wall adjacent the track. Racetracks also typically have walls protecting areas of the infield, especially along pit road. The walls are designed primarily for the purpose of protecting spectators and other persons near the track. However, the walls present a danger to the drivers in the event of a wreck. For example, when a race car impacts against the wall, even at a shallow angle, the car is suddenly decelerated resulting in significant damage to the car and potentially serious and sometimes fatal injury to the driver. In addition, cars impacting the wall tend to rebound back into traffic on the racetrack where the cars may be struck by other race cars traveling at high speeds.
Similarly, barriers flank roadways or serve as a median barrier between adjacent roadways. The barriers are generally in the form of permanent installations, such as heavy concrete barriers or metal guardrails. Of course, damage to impacting vehicles and potential injury to occupants of the vehicles is substantial at high speed due to rapid deceleration and sharp redirection of the vehicles by the barriers. Some guardrails have been designed to yield under impact and produce a reduced resistance to advancement of the vehicle in a selected direction. However, repair and replacement of guardrails as a result of impact damage is expensive and time consuming.
For the foregoing reasons, there is a need for an impact absorbing barrier which absorbs the impact forces of a moving object, such as a vehicle, colliding with the barrier for decelerating the object. The impact absorbing barrier should be effective for use as a wall on a vehicle racetrack, or as a barrier installed on a roadway. Ideally, the new impact absorbing barrier will absorb and dissipate the energy of the impacting vehicle while also redirecting the vehicle along the barrier to prevent the rebound of the vehicle into traffic. The new barrier should suffer little or no damage due to impact, but in the event of damage be easy to install and repair. The barrier should also be of minimal depth to prevent loss of roadway or track surface area.
Therefore, an object of the present invention is to provide an impact absorbing barrier which upon impact by a moving object, such as a vehicle, absorbs the impact energy for decelerating the vehicle.
Another object of the present invention is to provide an impact absorbing barrier which also redirects the vehicle at a low relative angle with the barrier.
A further object of the present invention is to provide an impact absorbing barrier which may be installed or replaced quickly and easily.
A still further object of the present invention is to provide an impact absorbing barrier which requires a small effective area for minimizing loss of roadway or track surface area.
According to the present invention, there is provided an apparatus adapted to be mounted to a rigid member for absorbing the energy of a moving object impacting the apparatus. The energy absorbing apparatus comprises a panel member formed of a deformable material. The panel member has a front wall, a rear wall and two side walls extending between and interconnecting the front and rear walls. The side walls are adapted to be angled relative to the rigid member in a direction of travel of the moving object when the panel member is mounted to the rigid member such that an impact on the panel member by the moving object will tend to deform the panel member toward the wall in the direction of movement of the object along the rigid member. This deformation allows the panel member to absorb the energy of the object for decelerating and redirecting the object subsequent to impact at a low angle relative to the rigid member. A support member is disposed in the cavity defined by the walls of the panel member and extends between and interconnects at least two of the walls for providing support to the panel member.
Also according to the present invention, an apparatus is provided to be mounted to a rigid member for absorbing the energy of a moving object impacting the apparatus. The energy absorbing apparatus comprises the above-described panel member and support member and means for mounting the panel member to the rigid member. In one embodiment, the mounting means comprises a mounting bracket having a front surface and a rear surface and is adapted to be attached to the rigid member so that the rear surface abuts the rigid member. The front surface of the bracket has a plurality of longitudinal channels for receiving correspondingly-shaped ridges on the outer surface of the rear wall of the panel member for coupling the panel member to the bracket.
Further according to the present invention, a barrier is provided for absorbing the energy of a moving object impacting the barrier. The energy absorbing barrier comprises an elongated rigid member and a plurality of the above-described panel members, including support structure. Means are provided for mounting the panel members to the rigid member at spaced intervals extending longitudinally along the rigid member so that at least a portion of the rear wall of each of the panel members directly or indirectly abuts the rigid member and the panel members are positioned in adjacent relation for allowing relative independent movement of adjacent panel members upon impact. Impact of a panel member by the moving object will tend to deform the panel member toward the wall and in the direction of movement of the object along the rigid member for absorbing the energy and retarding movement of the object and for transmitting the force of the impact to adjacent panel members such that the adjacent panel members are similarly deformed for successively absorbing energy and redirecting the object subsequent to impact at an angle relative to the rigid member less than the angle of impact.
A feature of the deformable material of the panel member is the physical characteristics which allow then panel member to withstand the impact while absorbing the energy of the moving object, including a durometer of 70 A and a Young""s modulus of 5000 lbf/in. These properties may be found in rubbers such as urethane and the like. The material may also be resilient so that the panel member returns to its original shape after impact by the moving object. The front wall of the panel member features an outer surface which is generally smooth and uniform. In one embodiment, compressible members fill the voids defined by the support member in the panel member cavity.
The energy absorbing panel member and barrier of the present invention is useful as a perimeter wall of an automobile racetrack or on a guardrail positioned adjacent a roadway. The barrier absorbs and dissipates the energy of a collision of a moving vehicle with a fixed surface while deflecting the vehicle safely along the fixed surface for reducing the potential injury to the driver of the vehicle and damage to the protected surface and the vehicle. Moreover, the barrier is designed to minimize installation time and maintenance. The mounting assembly has a minimal number of attachments which allows substantial portions of the barrier assembly to be removed and replaced quickly on the barrier in the event of damage The impact absorbing barrier of the present invention provides an alternative to rigid perimeter walls on racetracks or other areas including inner walls, pits and other spectator participant areas.